Lubricant



Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE LUBRICANT poration ofDelaware No Drawing. Application Iuly 27, 1937, Serial No. 155,916

6 Claims.

The present invention pertains to the improvement of lubricating oilsand greases and is particularly concerned with the addition of compoundsto hydrocarbon lubricants for the purpose of enabling those lubricantsto withstand very high pressures.

Modern advances in the art of automobile transmission design haveresulted in the subjection of bearing surfaces to loads much higher thanthose heretofore encountered. This trend has resulted in a demand forlubricants capable of fulfilling their lubricating functions under thenew conditions and of preventing scoring and seizure of lubricatedparts. To this-end, a large number of compounds have been synthesizedand added to the lubricants.

These compounds include, for example, lead sulphide, sulphurizedlubricating oils, chlorine derivatives of various organic compounds,phosphoric acid esters etc.

The object of the present invention has been to develop a new class oflubricants adapted for use as automobile engine and transmissionlubricants or as cutting oils. The invention consists specifically inthe addition to hydrocarbon lubricants of compounds of a class havingthe property of increasing the film strength of such lubricants greatlywhen added thereto in relatively small proportions.

The lubricants of the invention are synthetic products produced byblending a hydrocarbon lubricant with ammonium salts of the organic andinorganic acids. We have discovered that, when a small proportion of anammonium salt of an organic or inorganic acid is added to a hydrocarbonlubricating oil, the ability of that oil to continue to perform itslubricating function under conditions of high pressure and temperatureand low speeds is greatly increased.

The compounds of this class which have been found to effect. the mostmarked increase in the film strength of the lubricants with which theyare blended are the ammonium salts in which one or more organic radicalsare substituted for one or more hydrogen atoms of the ammonium radical.Thus, the amyl, di-amyl and tri-amyl ammonium chlorides have been foundto enhance very substantially the film strength of the hydrocarbonlubricants with which they are blended. Similar results have beenobtained by the addition of mono-, diand tri-butyl ammonium chlorides.Indeed, the entire class of mono-, diand tri-alkyl ammonium chlorides isuseful in the practice of the invention. Simi-- larly, mono-, diandtri-alkyl ammonium thiophosphates, phosphates, sulphates, nitrates andthe corresponding alkyl' ammonium salts of other inorganic acids may beused in the practice of the invention for increasing the film strengthof lubricants which are to be used under 5 extreme pressure conditions.

The mono-, diand tri-alkyl substituted ammonium salts of the organicacids may be used in a manner similar to-the salts of the inorganicacids discussed above. Thus, the mono-alkyl am- 10 monium salts offormicacid, acetic acid, propionic acid, butyric acid, valeric acid, caprolcacid, caprylic acid, oleic acid, stearic acid, palmitic acid, oxalicacid, laurlc acid, linoleic acid, sorbic acid, acrylic acid, hydracrylicacid, lactic acid, 15 glyceric acid, ricinoleic acid, chlor-acetic acid,carbamic acid and substituents thereof, and other saturated andunsaturated substituted or unsubstituted monoor poly-carboxylicaliphatic acids may be employed. The corresponding ammonium salts of thealicyclic acids, such as the naphthenic acids obtained from petroleum,quinic acid, hexhydrobenzoic acid, etc. may be similarly used.

The corresponding ammonium salts of the acids of the aromatic andheterocyclic series may also be used in the practice of the invention.Thus, the salts of aromatic sulphonic and phosphoric acids, benzoicacid, phthalic acid and anthranilic acid, salicylic acid, phenylaceticacid, cinnamic acid, furoic acid, pyridine sulphonic acid, pyridinemonoand di-carboxylic acid, etc.,

may be added to hydrocarbon lubricants to improve their film strength.

In short, the alkyl ammonium salts of the entire class of inorganic andorganic acids fall within the scope of the invention. The organic acidsalts employed may be the salts of aliphatic,

alicyclic, aromatic or heterocyclic acids and these acids may be monoorpoly-'carboxylic acids, amino acids, thio acids, hydroxy acids, acidssubstituted by carboxy radicals, etc. The ammonium radicals which formthe positive ions of the salts of any of the above acids used in thepractice of the invention may be substituted by alkyl radicals, by arylradicals, by alicyclic radicals or by heterocyclic radicals. Theinvention thus comprehends within its broad scope. the addition tohydrocarbon lubricants of ammonium salts of any acid provided suchammonium salts contain organic substituents for one or more of thehydrogen atoms attached to the nitrogen of the ammonium radical.

The ammonium salt added to the hydrocarbon lubricant to produce thelubricant'composition of the invention may be added in proportionsvarying widely depending upon the particular lubricant to be treated,the requirements of the use to which the lubricant is to be put and theparticular ammonium salt added to improve the film strength of thelubricant. The proportion of ammonium salt added will usually fallwithin the range between 0.1% and 5%, depending upon these factors.Preliminary experimentation will indicate the best proportion ofammonium salt to add in each individual case.

In case the lubricating oil to be treated is not thoroughly misciblewith the compound added to improve its film strength a common solventfor the oil and the added compound may be added in sufiicient quantityto afford a clear solution.

While the entire class of ammonium salts having organic radicalssubstituted for hydrogen of the ammonium radical is useful in thepractice of the invention, the salts in which three or four suchradicals are substituted for such hydrogen have been found to beparticularly useful, as will be seen from the following examples.

The following examples illustrate the practice of the invention:

Example 1 A sample of Mobiloil CW gear oil was tested in 9. Floydsplit-bearing lubricant testing machine. The oil was found to have afilm strength of '15 Floyd units (each Floyd unit is equal to 77 poundsper square inch, pressure) Example 2 Example 3 1% of triamyl ammoniumchloride was added to the gear oil of Example 1. The lubricant resultingfrom the compounding of the ammonium salt with the gear oil, when testedin the Floyd machine, had a film strength of over 600 Floyd units.

Example 4 1% of monoamylammonium chloroacetate was added to the gear oilof Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of 10 Floyd units.

Example 5 1% of tributylammonium chloroacetate was added to the gear oilof Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, hada-film strength of over 600 Floyd units.

Example 6 3% of diamylammonium diamyldithiocarbamate was added to thegear oil of Example 1. The

lubricant resulting from the compounding of the ammonium salt with thegear oil, when test ed in the Floyd machine, had a film strength ofFloyd units.

Example 7 1% of monoamylammonium chloroacetate was added to the gear oilof Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of 100 Floyd units.

Example 8 0.5% of tributylammonium bromide was added to the gear oil ofExample 1. The lubricant resulting from the compounding of the ammoniumsalt with the gear oil, when tested in the Floyd machine, had'a filmstrength of Floyd units.

Example 9 0.2% of tributylammonium sulphate was added to the gear oil ofExample 1. The lubricant resulting from the compounding of the ammoniumsalt with the gear oil, when tested in the Floyd machine, had a filmstrength of 100 Floyd units.

I Example 10 0.5% of triamylammonium nitrate was added to the gear oilof Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of Floyd units.

Example 11 0.5% of tributylammonium valerate was added salt with thegear oil, when tested in the Floyd machine, had a film strength of Floydunits.

Example 12 0.5% of tributylammonium p-toluene sulfonate was added to thegear oil of Example 1. The lubricant resulting from the compounding ofthe ammonium salt with the gear oil, when tested in the Floyd machine,had a film strength of 100 Floyd units.

Example 13 Example 15 0.2%laurylammonium chloride was added to the gearoil of Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of 100 Floyd units.

Example 16 0.2% tributylbenzylammonium chloride was added'to the gearoil of Example 1.. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of 100 Floyd units.

Example 17 0.2% tributylhydroxyethyl ammonium chloride was added to thegear oil of Example 1. The

lubricant resulting from the compounding oi the ammonium salt with thegear oil, when tested in the Floyd machine, had a' film strength of 100Floyd units. I

7 Example 18 0.5% of a substituted ammonium salt formed by reactingtributylamine and benzene sulionyl chloride was added to the gear oil ofExample 1. The lubricant resulting from the compounding of the ammoniumsalt with the gear oil. when tested in the Floyd machine, had a filmstrength oi 100 Floyd units.

Example 19 0.2% .of a substituted ammonium salt formed by reactingtributylamine and chloroacetic acid was added to the'gear oil ofExample 1. The lubricant resulting from the compounding of the ammoniumsalt with the gear oil, when tested in the Floyd machine, had a filmstrength or 100 Floyd units.

Example 20 0.5% tributylammonium alphachloropropionate was added to thegear oil of Example 1., The lubricant resulting from the compounding-oithe ammonium salt with the gear oil, when tested in the Floyd machine,had a film strength of over 600 Floyd units.

Example 21 0.5% of an ammonium salt formed by reacting tri-butylamineand dichloroacetic acid was added to the gear oil of Example 1. Thelubricant resulting from the compounding of the ammonium salt with thegear oil, when tested in the Floyd 40 machine, had a film strength ofover 600 Floyd units.

Example 22 0.5% ammonium salt formed by reacting tributylamine andtri-chloroacetic acid was added to the gear oil of Example 1.Thelubricant resulting from the compounding of the ammonium salt withthe gear oil, when tested in the Floyd machine. had a film strength of100 Floyd units.

Example 23 Example 24 00 A substituted ammonium salt formed by reactingtri-butylamine and beta chloropropionic acid was added to the gear oilof Example 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floyd machine, had afilm strength of 100 Floyd units.

Example 25 0.5% of a substituted ammonium salt formed by reactingp-chloroaniline and alpha chloropropionic acid was added to the gear oilof Ex-' ample 1. The lubricant resulting from the compounding of theammonium salt with the gear oil, when tested in the Floydmachine, had afilm strength of 400 Floyd units";

Example 26 A sample of D. T. E. oil, a highly refined paraffinic oil,was tested in the Floyd split bearing lubrication testing machine. This011 was ,also found to have a film strength of 75 Floyd units.

Example 27 One percent of the reaction mixture formed by reactingdioctyl hexyl amine and mono chloro acetic acid was dissolved in the D.T. E. oil. The resulting lubricant, upon being tested in the Floydmachine, was found to have a value of over 600 Floyd units. The samematerial, upon .being' tested with the Almen machine, withstood the fullload of 15,000 pounds per square inch without damage to the bearing.

Example 29 One percent of the reaction mixture formed by reacting diamyllaurylamine and chloroacetic acid was dissolved in the D. T. E. oil. Thelubricant so obtained had a value of over 600 Floyd units. The samematerial, upon being tested with the Almen machine, withstood the fullload of 15,000 pounds per square inch without damage to the bearing.

. Example 30 One percent of the reaction mixture formed by reactingdibutyl aniline and chloroacetic acid was dissolved in the D. T. E. oil.The resulting lubricant was found to have a value of over 600 Floydunits. The same material, upon being tested with the Almen machine,withstood the full load of 15,000 pounds per square inch without damageto the bearing.

Example 31 .5% of the reaction mixture formed by reacting tributylaminehydrochloride and cupric chloride was suspended in Mobiloil CW. Uponbeing tested, it was found that this material had a film strength ofFloyd units.

Modifications will be obvious to those skilled in the art and we do notwish to be limited except by the scope oi the subjoined claims:

By the term inorganic hydro-halogenic acid in the appended claims it isintended to include those acids which result solely from the combinationof halogen atoms and hydrogen atoms as, for example, hydrochloric acidand hydrobromic acid.

We claim:

1. A lubricating composition comprising a hydrocarbon oil and a smallproportion of a trialkyl ammonium salt of an inorganic hydrohalogenicacid.

2. A lubricating composition comprising a hydrocarbon oil and a smallproportion of a triallgvl ammonium salt of an inorganic hydrohalogenieacid, the allwl radicals of said ammonium salt containing between threeand seven carbon atoms.

3.-A lubricating composition comprising a'fhydrocarbon oil and a smallproportion of an unhydroxylated tri-alkyl ammonium salt of an inorganichydrohalogenic acid.

4. A lubricating composition comprising a hy 6. A lubricatingcomposition comprising a. hydrocarbon oil and a small proportion of analkyl drocarbon oil and a small proportion of a tetraammonium salt of aninorganic hydrohaiogenic alkvl ammonium salt of an inorganichydrohaloacid. genic acid.

5. A lubricating composition comprising a by JOHN F. OLIN. drocarbon oiland a small proportion of an un- ROLAND H. GOSHORN.

hydroxylated alkyl ammonium salt of an. inorganic hydrohalogenic acid.

